In producing crops, many chemicals are used so as to promote plant growth and to improve a quality of the crops. A lot of chemicals are abused, such as chemicals for promoting the seed germination, plant growth or fruit ripening, chemicals for protecting the plant against various pathogens and chemicals for improving the preservation and storage of the crops harvested.
In order to solve the above problem, a variety of organic cultivation methods are recently developed. As the interest in the health is tremendously increased, the vegetables organically grown are spotlighted. However, it is difficult to produce the crops, which are quantitatively and qualitatively excellent, only with the existing organic cultivation methods.
It has been known that lysophosphatidylethanolamine plays a very important role in the ripening and senescence of the fruit. It has been known that the senescence of the leaves and the fruits of tomato are suppressed with the treatment of lysophosphatidylethanolamine. It has been also known that the preservation time of the fruit of tomato can be prolonged with the treatment of lysophosphatidylethanolamine after the harvest (see U.S. Pat. Nos. 5,110,341 and 5,126,155). In addition, it has been known that if an apple is treated with the lysophosphatidylethanolamine, the formation of anthocyanin in the skin thereof is promoted and the loss of firmness during the preservation period of the apple harvested is suppressed. It is known that these effects are related to functions of lowering a respiration rate of fruits such as an apple, cranberry, tomato and the like and promoting or suppressing the formation of ethylene gas (Farag, K. M. and J. P. Palta, ‘Stimulation of Ethylene Production by Erea, Thidiazoron, and Lysophosphatidylethanolamine and Possible Sites of This Stimulation’ Annual Meeting of the American Society of Plant Physiologists, April 1989).
The lysophosphatidylethanolamine solution having a concentration properly adjusted is often used as the means for prolonging a lifetime of the cut flower (HortScience 32(5): 888-890, 1997).
In the mean time, the silicone, which exists in the plant, is known to change the metabolism of the plant. Specifically, if the plant is treated with the silicone, an amount of chlorophyll is increased and the plant growth is promoted. In addition, it is supposed that the silicone protects the plant against the damage from disease and harmful insects and helps the normal growth, occurrence, survival and reproduction (S. Y. Wang, et al., Journal of plant nutrition, 21(1), 157-167 (1998); Emanuel Epstein, Annu. Rev. Plant Physiol. Plant Mol. Biol. 50:641-64 (1999)).
In addition, in order to promote the plant growth and to improve the preservation thereof, it has been suggested a composition including potassium silicate, sodium silicate, potassium carbonate, sodium carbonate, sodium bicarbonate, etc. and a method for manufacturing the same (see U.S. Pat. No. 6,284,709). It is disclosed that if the plant is treated with a composition including potassium silicate, sodium silicate, potassium carbonate, sodium carbonate, potassium chloride and reducing sugar, the plant growth is promoted, the propagation of microorganism is suppressed, the physical properties are improved and the preservation of the agricultural products is prolonged.
However, it is impossible to effectively promote the plant growth only with the above methods and the preservation property is not attained in a satisfactory level. Accordingly, it is needed an alternative capable of harvesting the fruit of high quality in a large amount and preserving the harvested fruit for a longer time while less using the chemicals harmful for the body and the environments.